JavaScript中有重复项时如何从数组中删除某些项
我们需要编写一个包含一组文字的JavaScript函数。我们的函数应该返回一个新数组，其中所有三元组都已过滤。
为此的代码将是-
const arr1 = [1,1,1,3,3,5];
const arr2 = [1,1,1,1,3,3,5];
const arr3 = [1,1,1,3,3,3];
const arr4 = [1,1,1,1,3,3,3,5,5,5,5,5,5,5,5,5,5,5,5,7,7];
const removeTriplets = arr => {
const hashMap = arr => arr.reduce((acc, val) => {
if(val in acc){
acc[val]++;
}else{
acc[val] = 1;
};
return acc;
}, {});
let res = [];
let obj = hashMap(arr);
for(let key in obj){
for(let i = 0; i < obj[key] % 3; i++){
res.push(key)
};
}
return res;
}
console.log(removeTriplets(arr1));
console.log(removeTriplets(arr2));
console.log(removeTriplets(arr3));
console.log(removeTriplets(arr4));控制台中的输出-
[ '3', '3', '5' ] [ '1', '3', '3', '5' ] [] [ '1', '7', '7' ]